This 1976 issue from Nicaragua belongs to the commemorative series Estampillas Raras y Famosas ("Rare and Famous Stamps"). It reproduces the legendary 1854 Western Australia 4d Swan "Inverted Frame", one of philately’s most celebrated errors. The design shows the green swan vignette framed by an inverted border, a mistake that makes the original among the rarest Australian classics. Nicaragua honored this world rarity with a 2 centavos postal stamp, printed in brown with the replica at right. A must-have item for collectors of error reproductions, thematic swan issues, and Nicaragua’s philatelic tributes to famous stamps.